Ship had a pumproom explosion discharging at Fawley, killing two.
The cause was traced to the failure to install
two locking screws when the pump was overhauled in 1989.
This allowed the first stage impeller nut to back off.
This led to vibration,
oil escaping into the pump room thru the top mechanical seal,
and igniting.
The pump overhaul was done by a contractor,
but MAIB correctly blamed the contractor, and the owner.
About Class, all it says is "workmanship was not up to the standard of Lloyds".